Wow, that's close! Mine are 18 months apart so I can give an idea of what to expect. (A close age gap gives pretty much the same situation no matter how close it is.)Do what you can to get your son to understand what's about to happen. It'll be a little more difficult since he's so young and he may not understand your words as well. The idea of a new sibling is pretty abstract.If you know other people who have younger babies set up a play date so that he can start interacting with babies. You can also get him a doll or stuffed toy that can be his baby to take care of. This will help bring out his nurturing side and will teach him to be gentle with babies. At play dates or with a doll you can also get him used to the idea that you will be taking care of another child so he will be better prepared for someone else having your attention.One thing that I think really helped us was having our daughter spend our last night in the hospital with us. (It wasn't planned, my famiy just crapped out on babysitting her and we had no other option.) She got to meet her baby brother and understood better that he was a member of our family. I think it worked better than just brining him home as a surprise. As far as what life will be like, it's going to depend a little on how well your son reacts to having a baby in the house. But, it's really not that crazy. Having "two in diapers" really isn't that big of a deal. After my son was about a week old my daughter isisted on taking baths with him. I put his baby bathtub in the big bathtub and filled the both. They loved being able to play and bond together. My daughter also loved being a helper. She would bring us blankets, bottles, pacifiers, etc. Being able to helo take care of him made her less jealous. Of course, your son may not be able to do those things if he's not walking yet. Once your daughter is sitting up and crawling they'll be able to play together better and that's when they'll become very close. My kids have been best friends since that point. Your son will probably try to play earlier, just make sure you don't have any hard toys out in case he accidently throws them or tries to hit her. Ultimately, your kids will have an awesome relationship because of the closeness in age. Things can be a little tricky at first but as long as your son is prepared for his new sister things shouldn't be too difficult. Having two kids so close int heir development makes things a lot easier as they get older.